US4507356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Moisture-permeable sheets
Assignee: Aderans Co Ltd
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Filing: 1982-09-30
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Granted: 1985-03-26
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Expires: 2002-09-30
Abstract
Abstract A multi-layer sheet used particularly as a wig base includes a lowermost layer of a poly-α-amino acid derivative, an uppermost layer of a polyurethane elastomer and woven or knitted fabric of nylon or polyester as reinforcing material, said layer of polyurethane elastomer alone or both said layer of polyurethane elastomer and said layer of poly-α-amino acid possessing moisture permeability. To prepare the sheet, finely-divided, water-soluble salt particles are dispersed in the polyurethane elastomer alone or both in the polyurethane elastomer and the amino acid derivative in the presence of a titanate coupling agent serving as a dispersant.
Inventors
- 👤 Nobuo Watabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:56
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B32B27/40; B32B2305/00; B32B2305/02; B32B2305/026; B32B2307/00; B32B2307/70; B32B2307/726; Y; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249978; Y10T428/31504; Y10T428/31551; Y10T428/31565; Y10T442/00; Y10T442/10; Y10T442/102; Y10T442/172; Y10T442/174; Y10T442/20; Y10T442/2041; Y10T442/2098; Y10T442/2107
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
56 words
A multi-layer sheet comprising a first layer of a poly-α-amino acid derivative film having embedded therein a reinforcing material selected from the group consisting of woven fabric and knitted fabric made of nylon or polyester, and a second layer of a polyurethane elastomer film, at least one of said first and second layers being moisture permeable.
Claim 2
Dependent Claim
56 words
A multi-layer sheet comprising a first layer of a poly-α-amino acid derivative film having embedded therein a reinforcing material selected from the group consisting of woven fabric and knitted fabric made of nylon or polyester, and a second layer of a polyurethane elastomer film, at least one of said first and second layers being moisture permeable.
Claim 3
Dependent Claim
21 words
The sheet as recited in claim 1, in which said moisture permeability is between 500 and 2000 g/m 2 /24 hr.
Claim 4
Dependent Claim
14 words
The sheet as recited in claim 1, wherein said poly-α-amino acid derivative is poly-α-methyl-L-glutamate.
Claim 5
Dependent Claim
17 words
The sheet as recited in claim 1, wherein said polyurethane elastomer film contains a multiplicity of micropores.
References Cited (Backward Citations)
US4425395A
Cited
US4436570A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-03-25 | 1988-09-24 | 1989-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-03-25 | 1992-09-24 | 1993-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-03-25 | 1996-09-24 | 1997-03-26 | $7700.00 | Window Closed / Lapsed |